*{
    padding: 0;
    margin: 0;
    background-color: hotpink;
}
.div1{
    /*width: ;*/
    /*background-color: burlywood;*/
    color: black;
    height: 60px;
    text-align:center
}
.div2{
    margin-top: 80px;
    background-color: black;
    width: 100%;
}
.div3{
    margin-left: 270px;
    /*background-color: aqua;*/
    height: 400px;
    width: 200px;
    float: left;
}
.div4{
    background-color: coral;
    color: white;
    height: 80px;
    width: 200px;
    font-size: 20px;
    font-family: "新宋体", serif;
    text-align: center;
}
.div5{
    float: left;
}
iframe{
    height: 1200px;
    width: 1200px;
}